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Message-ID: <1518719968.13961.32.camel@gmx.de>
Subject: Re: [RFC 1/2] sched: reduce migration cost between faster caches
 for idle_balance
From: Mike Galbraith <efault@gmx.de>
To: Steven Sistare <steven.sistare@oracle.com>,
        Rohit Jain <rohit.k.jain@oracle.com>, linux-kernel@vger.kernel.org
Cc: peterz@infradead.org, mingo@redhat.com, joelaf@google.com,
        jbacik@fb.com, riel@redhat.com, juri.lelli@redhat.com,
        dhaval.giani@oracle.com
Date: Thu, 15 Feb 2018 19:39:28 +0100
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On Thu, 2018-02-15 at 13:21 -0500, Steven Sistare wrote:
> On 2/15/2018 1:07 PM, Mike Galbraith wrote:
> 
> >> Can you provide more details on the sysbench oltp test that motivated you
> >> to add sysctl_sched_migration_cost to idle_balance, so Rohit can re-test it?
> > 
> > The problem at that time was the cycle overhead of entering that LB
> > path at high frequency.  Dirt simple.
> 
> I get that. I meant please provide details on test parameters and config if
> you remember them.

Nope.  I doubt it would be relevant to here/now anyway.

	-Mike